Fifteen patients with fibromyalgia syndrome were given EMG-BFB (biofeedback) training sessions because of persistent aches after one year of monthly courses of NSAID. A long-lasting clinical benefit was observed in 56%. The improvement was found in those without overt psychopathological disturbances. In fact, a subgroup of clinically depressed patients responded poorly. Our findings were confirmed in a controlled study. Six patients were allocated into "true EMG-BFB" and 6 into "false EMG-BFB" treatment in a blinded fashion. The rheumatological assessment revealed a significant improvement in most of the variables only in the "true EMG-BFB" group.